


A Demon Comes Knocking

by Neeckin



Category: Original Work
Genre: Bad end, Brainwashing, Demonic Corruption, F/F, Sister/Sister Incest, Transformation, Yuri
Language: English
Status: Completed
Published: 2020-06-22
Updated: 2020-06-22
Packaged: 2021-03-03 23:01:37
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,307
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24863497
Author URL: https://archiveofourown.org/users/Neeckin/pseuds/Neeckin
Summary: During a great conflict, Faris and her sister Ceris stand guard at a small town, a bulwark against whatever hides in the nearby forest. They think that they can stand against it, but one night they are proven wrong.
Kudos: 13





	A Demon Comes Knocking

A Demon Comes Knocking

Faris and her younger sister Ceris were exhausted. The knight and Priestess had spent the entire day doing patrols along the small frontier towns border, the work of 12 people usually. The war against evil continued to be costly, and their kingdom could not spare more for protection of a town that was so close to the forest. The vast woods were cursed lands that monsters and untold horrors dwelled in. Faris began removing her heavy plate armor as soon as they locked the door to their dwelling. The small shack was a small way from the town, a bulwark of sorts as it sat closest to the forest. There would be no leering eyes on them from the men of the village.

Setting her armour next to her longsword and shield in the corner Faris rolled her shoulders, her powerful muscles weary from the day's work. The simple tunic and pants she wore at least allowed the cool night air to provide a small relief to the redhead. On the other side of the bedroom the knights sister also disrobed, revealing her simple underwear and bra beneath her priestess robes. Tossing them aside the younger blonde lit a candle. The two sat in silence for a few moments, the dull, flickering candlelight dancing shadows across them.

Faris looked at her sister. While she had the scars and body of a warrior, her sister had the body of a divine, her long golden hair and rounded face was angelic. Coupled with a body she had seen catch the eye of several men and women in the town.

Do you think there will be another attack tomorrow sister?” Ceris asked, breaking the silence.

Faris frowned, already they had fought off the attacks since they had arrived 2 weeks ago, shadow thralls lurching out of the forest, more with search assault. The creatures were   
magical and dim witted, which meant there was a greater evil behind them, but what their goal was Faris was unsure.

“Perhaps,” was all Faris said in response.

Despite the grim response Ceris patted her older sister's shoulder, “ Have faith sister, soon we will get reinforcements and move on from this town.”

The younger sister rose, “and besides, to hold a town on our own will do wonders for our reputation.”

A brief thought of leading a platoon of soldiers, a captain’s declaration adorning her around passed through Faris's mind, but she pushed it away. Her duty was to protect her charge, nothing more.

The two soon turned in for the night, extinguishing the candle and hoping a night's rest would come to them soon. But that was not to be. Not an hour after closing their eyes Faris ‘s well trained instinct pulled her awake. In moments she was on her feet, the sounds of snapping twigs and grass just outside their door altering her to a looming danger. She managed to shake her sister away when the wooden door of their small house was torn off its worn hinges. Several shadow thralls stumbled into the room, their gas like, misshapen bodies standing out even against the near pitch darkness of the night.

Faris grabbed the first to come into reach and threw it back at the others, the creatures stumbling onto a pile. The act bought her ample time to grab her sword and shield, and the now roused Ceris to summon holy light to illuminate the sudden battlefield. The fight itself was quick, with Faris trusting her longsword like a spear, and crushing the creatures with her shield. All the while Ceris picked the fee more that came into the door with bolts of holy light to their forms, each thrall dissolving into nothing once they were bested.

Once the final creature fell and no further noise could be heard the sisters took a moment to catch their breath. Without a word they both donned their combat gear and exited their dwelling to begin a patrol for any further attacks. The pair hit no more the 30 steps from their house when Faris stopped Cerid and pointed out a figure emerging from the forest. It was obviously female but neither sister would call it human. Thick horns curved out from the side of her head, running forward next to her skull and ending in a sharp angled pointing upwards. Her large leathery wings and a long tail all identified her as one thing, a demon.

Faris stepped forward, positioning herself between her sister and the approaching demon. She had heard countless stories of the female ones snatching magic users for some unknown purpose. On her honor as a knight Faris knew she would do everything to stop the creature.

“Ceris, run to the village and tell them about this and hide,” The knight said, her voice slow and steady, so that each word was understood, “I will follow once U have chased her off, do you understand?”

She heard her sister whisper a response and run. By then the demon was no more the 10 strides from Faris, the knight able to see the creature wore dulled black leather armor and welded no weapon, its eyes almost glowing in the night.

“So you two are the ones who defeated so many of my shadow thralls,” the demon said as she came to a stop, her tone wasn’t one of anger, but excitement.  
Faris took a defensive stance, which brought a chuckle from the demon.

“Now then…”the horned woman trailed off, blackness pooling into her eyes for a few moments, “Faris I believe?

The knight was feeling increasingly wary of her situation as the demon took another step towards her.

“You can relax that sword arm my powerful knight, I have no desire for your sister Cerin tonight the demon cooed,” I am Lilith, and tonight you will have my full attention.”

Faris attention was broken when she heard her sister shouting, and broke eye contact to look behind her, seeing her sister sprinting back from the village. In those precious few moments Faris felt an iron grip on the nape of her armour and a great force pulled her backward. She did not fall, and instead felt herself being continuously pulled back towards the first at a great speed, her weapon falling from her grip as Ceris and their home quickly grew smaller. Then darkness overtook her as she lost consciousness.

Faris awoke slowly, consciousness coming slowly, and strange sensations confusing her. Eventually she opened her eyes to find she was naked in a pool, carved into smooth granite and lit by several torches adorning the walls. The water was unnatural looking, black with glowing white specks, a shifting visage of a night sky. A sensation of a hand on her shoulder caused the large women to look behind her, and jump when she saw she was sharing the pool with the demon, Lilith. The creature was also nude, her demonic features standing out more against her pale skin.

The demon smiled and offered Faris a cup, the liquid inside similar looking to what they were sitting in. Looking to stall time Faris took it without a word and drank it, desperately trying to think of an escape, and eyeing the room’s door.

The liquid tastes like smoke, and almost made Fsris cough. And when she looked up the demon had vanished.

“Now it is just the two of us,” The demon whispered, suddenly right behind her, “ and a chance to explore such a wonderful body.”

A small gap fell from Fameris"s mouth as she felt gentle fingers trace scars along her back. For a moment she thought to stop the demon, but It felt good, really good. And then she felt a kiss on her neck and the few fighting thoughts melted away, there was no harm in indulging a bit, the demon didn’t seem to mean any harm after all. A moan of pleasure was followed by several more kisses to Faris neck, the demon having wrapped her legs around the giant woman's waist.

“It feels good, right? “Lilith added between kisses, “do you want more?”

“Gods yes,” Faris said, her tone one of near begging.

For a moment Faris took notice of how her thought seemed to be drifting towards pleasure, to sex. It had been a long time since she had taken someone to bed, or even masturbated, but even then she shouldn’t be this aroused. Perhaps there was something in the water she drank. That thought however never finished as Faris felt Lilith’s finger slowly enter her. Almost by investing the giant women bargain rolling her hips, wanting more. She could feel a building pressure she hadn’t experienced in a long time, and longed to feel that rush of mind numbing pleasure.

“I know you want to be a true knight Faris, free of the shackles so you can become something greater, and I can give it to you,” Lilith whispered into Faris's ear.

For a moment the woman was confused, the exact circumstances of her situation having been lost to her. Even still she did not stop, bouncing on Lilith’s fingers and playing with her beats, whatever would bring her orgasm faster. Some small part of her realized she was fading quickly, the ancient barriers of control in her mind falling over by the second.  
“And I know you want to cum to cum so very bad, to experience the rapture of pleasure” Lilith cooed, “you can have both, just offer me your soul, and total obedience.”  
Faris was only half listening, everything focused on cuming, on reaching that climax, nothing else seemed to matter . Neither could see. But darkness began to flood Faris's eyes, quickly turning them into black orbs, a showcase of the corruption the water was having on the knight's mind.

Lilith asked again, looking at her pretty for an answer. The proud knight was a mess, and a shadow of herself, black eyes looking at nothing as her mouth Hung open a bit, her tongue hanging out as she panted and moaned in lust, still out of reach of her climax.

“Please, let me cum,” the Amazonian woman mumbled between moans.

“Do you agree to my terms Faris?” Lilith asked, her tone adding great weight to the question.

There was a pause before Faris said yes.

The orgasm hit the knight like a thunder shock, her whole body going rigid as waves of pleasure flowed through her body. There was no place for thoughts as mind blanking pleasure flooded her brain, only animalistic instinct, her body trying to ride out the pleasure for as long as possible, demanding more of it. All the while Lilith brought her into a deep kiss, the demon's eyes glowing bright.

As the orgasm started to fade Lilith broke the kiss, and Faris watched as a glowing thread connected the two, and one thing came to mind, her soul. The knight had the chance to attack, to do anything. But instead she obediently stayed still, masturbating with wide eyed pleasure as she watched Lilith draw out the last of her very soul and consume it. The pure white essence, everything that was Faris burnt away, nothing more then another meal for the demon. With her last moments the knight Faris brought herself to orgasm once again, the last shreds of the human known as Fairs falling away with only a soft gasp of pleasure as her final mark on the world.

Lilith watched in bemusement as the once proud and powerful knight gave up everything for a final taste of pleasure. But with the fun concluded and the woman's soul consumed there was much to do. Lilith took a moment to relish her new amazon’s body , its tall, muscular form, ample breasts and butt with an order the nameless human followed her mistress obediently out of the pool, her face that of a mindless slave. A fitting position for such a weak willed knight.

Lilith spent the rest of the night in absolute delight. The binding ritual had gone perfectly, and the warrior woman was now bound to her. The thralls own independence, the will and spark of humanity having been so delightful consumed, leaving just its immovable obedience. The souls had been a great boost to Lilith’s power, enhancing her status as a demon. The moonlight hours had been spent using the massive women’s body for seemingly endless pleasure, the once bright eyes of a keen warrior now dull black. Currently Lilith was enjoying looking into those as Faris gave her vaginal another round of attention, her tongue mange to find every perfect place. Lilith shuttered as she felt another orgasm run through her body, holding Faris in her so the thrall could get nice and deep before they left. The sun would soon rise, and there was much to do.

With a wave of her hand Lilith’s clothing returned to her body, tight leather pants and shirt, the magic fixing her disheveled hair as a bonus. The two left Lilith’s opulent bedroom, Faris following behind her and entered the lair's main hall. Lilith’s home was not a grand castle, but served its purpose, carved into a mountain. The tiled floor and smooth stone walls housing a carved wood door to the other rooms, to the left and right the ritual pool and the living area and kitchen, and across the floor a simple black iron door leading outside.

The two made their way to the living area, the first door of the hallway led to a kitchen and the rest to bedrooms and other requirements. Though Faris was a thrall she would require sleep, food and training to maintain her combat skill, as well as improve. Lilith had bit lied to the woman, she would become a powerful knight at her side.

The main living area stretches into a long hallway, larger than what should be possible for its location. Far below in the stone depths Lilith has uncovered a well of power and attuned herself to its flow. Within the walls of her lair she had total control and power, even bending the space of reality as she saw fit, molding it like clay, and bringing forth all manor of objects to fill her home. There were of course limits to it all , but it allowed her to carve out a place for her in the world.

The two passed 3 doors before Lilith stopped at a red one, the symbol of a sword decorating its front. The two entered and Lilith stepped aside so that her thrall could look at the room.

“This my Knight, will be your space, to train and learn, as well as rest when you are not needed.” The demon explained to Faris.

Faris’s expression did not change as she took in the large room’s items and amenities. The room housed a bed that was already made, her armour and clothing on top of it. Next to it stood a large bookshelf filled with books, the titles on the spines identifying them as a mix of combat and weapon instructions and tutorials, as well on books on how to properly serve and please a mistress. Next to it was a blacksmith work station that took up a full corner of the room, with all the tools required for maintaining and repairing weapons and armour, with a variety of books on the subject sitting in a pile next to the station. A small door next to the bed led to a side room, outfitted for proper training and practice for combat. In truth Lilith had several rooms set up much like this, her original plan having been to capture townsfolk, enthrall them and train them up as warriors. The chaos of the war made the perfect time to expand her power.

Faris took a few moments looking at her accommodations before turning back to Lilith.

“Thank you Mistress , it is perfect,” she said simply, a small smile breaking past her stoic expression.

Faris quickly adorned her clothes and armour, listening to her Mistresses plan. The goal was simple, capturing and corrupting Ceris. Lilith had plans other than enthralling for the holy magic user. For Lilith it was a simple plan for smoke and mirrors, tricking the young women and ensnaring her quickly. The two made their way out of the layer in, with Liluth telling her thrall the plan. With a simple flash of magic the two found themselves exiting the first in a matter of minutes. The damaged house was soon in view, its turn doorway left open as if it had. Been left untouched from the night's events.

Lilith used her magic to vanish as they approached, and Faris entered the home to look around. To their luck, Ceris sat on her bed within, half dressed and looking disheveled. The young woman held Faris's shield in her arms as if cradling it. When she turned to look at the door however it fell to the floor and was forgotten. The two came together and embraced, the larger warrior holding her sister tightly in her arms. Without a sound Lilith reappeared behind Ceris and gave a nod to her thrall to begin. Faris eased Ceris to the floor, never breaking the hug, and then Lilith touched Ceris shoulder.

The reaction was instant as Ceris looked upon the demon, and the possibility that her sister had gotten away vanished under the dread of her situation. Without a second thought Cetis called upon a holy spear while struggling in her sister's grip. To her horror though the bolt hit the demon, and did nothing. Its pure holy light turning to black smoke against the demon's chest.

“You see Ceris, your god has abandoned you,” Lilith cooed,” join me, Lilith and revel in corruption and true power “

Ceris could only stare, briefly acknowledging her sister's grip leaving. After a few moments of silence on the floor the sound of falling metal drew the priestess attention back to her sister, who to her shock was nude. The warriors sculpted body on full display,

“Best we just get to the fun then.”Lilith chuckled and summoned her magic.

In an instant both Ceris and the demon's clothing vanished, all three now naked, the days warmth kissing Ceris’s skin.

It was all too much for Ceris and she tried to get up and run. But again felt the tight grip of her sister. Ceris turned to hook at her as Faris sat Ceris down on her lap, her large butt pressing against her sister's vagina.

“Please Faris,” Ceris begged as she turned to look at her sister “You have to snap out of it, grab your sword, fight her, anything please!”

Faris said nothing, her face stoic, then after a few moments she brought her sister in for a deep kiss. At first Ceris tried to pull away but her struggles were futile. One of Faris's hands slowly made it down to her sister's vagina, and after a few experimental strokes her fingers parted the lips and sank into her sister's depths. A moan escaped Ceris throat at the sexual assault on her senses, and Faris used the opportunity to pull Celia close, grinding her wet pussy again to her sister fat ass.

At the same time Lilith exhaled into her hand, a small amount of thick black smoke staying in her palm. It was an ancient magic but what was needed. Faris watched her Mistress’s reach out and calmly put her hand to Cetis head, the black smoke vanishing into her head. The young woman's eyes rolled back as if she was cumming hard. Faris broke the kiss and allowed her Mistress to guide Ceris mouth to her waiting pussy. Ceris did not resist and began to eat the demon out, her eyes unfocused and glazing over from the corruption that was overwhelming her mind.

“You can feel it can't you?” Lilith asked as she ran fingers through the womens hair, already seeing signs of corruption,”I put a piece of me in you and it is going to corrupt you right down to your soul, and it will be the best feeling you've ever had.”

The priestess squirmed, obviously experiencing another orgasm as her eyes opened wide for a moment before settling back to the glassy, lost look. Already the white of her eyes where turning a deep red. Lilith relished the feeling of the holy women abandoning her morals to pleasure her while getting fucked by her sister. If there was even a shred of coherent thought left in Ceris’s mind it was quirky consumed by a fog of pleasure. Looking up she barely noticed Lilith draw a symbol over her own womb, or as it began to glow. 

“Show your submission by kissing the seal and complete the ritual “ Lilith commanded,”and you shall become my apprentice.”

There was nothing left of Ceris mind that could say no, or point out that she was about to use dark, taboo magic. Only the soft gasp from cumming as she brought her lips to the seal, kissing the demon's soft belly.

There was a flash of darkness, the force of which knocked all three to the ground. Lilith was the first to rise and smiled at the sight before her. Demonic attributes covered Ceris, the former human. A long tail and wings as well as curved horns now adorned her corrupted form. The priestess was now a demon like her.

Slowly the two sisters rose, Faris towering over her newly demonic sister, casting a shadow over her.Ceris gave her sister a soft smile and hugged her, her new tail slowly bobbing around behind her. Faris placed a hand on her sister's head, and gave the younger women a few pets. Lilith stepped over to Ceris, placing a hand on her shoulder.

“Now then,” She said with a cheery tone, “I think it is best you two gather your things and we leave.”

Faris gave her Mistress a stern node and began putting her armor back on. Ceris however looked at the demon.

“Thank you Lilith, I can’t even describe how good this feels,” She said softly, “I know it is probably just the corruption having changed my brain but it feels right wanting to obey you.”

Lilith gave Ceris a wide grin and offered to show Ceris a new spell. The young demon was happy to learn, and so as Faris collected the pair's belongings and keepsakes for travel Lilith showed Ceris how to use her new magic to give the pair back their clothes. Both got a chuckle as the inexperienced demon accidentally summoned their clothes on the other but quickly got the hang of it before her powers ran dry. The three left the human village behind for good and with Liliths magic arrived at her layer in mere minutes. Ceris stopped at the main room and marveled at the opulence of such a remote home while Faris hurried away at Liliths call to put away the luggage.

The two demons stood alone and Lilith could not help but stand next to Ceris, the young demon's wide hips squishing against the slender demon's body. Ceris let out a surprised gasp as she felt Lilith run her hand along her ass, and feel their two tails intertwine. 

:”You are my apprentice now as well as my obedient plaything, understand?” Lilith asked

Ceries nodded with a drifting look in her softly glowing eyes.

“Good, then strip,” Lilith commanded, “I didn’t get my fill at the village.”

Ceris did so without hesitation. The thought of obeying her mistress made her pussy wet with anticipation. Her clothes were quickly tossed aside, and she dropped to her knees, looking at her Mistresses already exposed vagina with anticipation. Without needing to be ordered she buried her tongue deep into Lilith, her hands roaming the demon's breasts and clit, searching for every way to give more pleasure. Lilith moaned with pleasure, both hands holding Ceris in place.

“Doesn't this feel good?’ Lilith asked between gasps of pleasure, “Doesn't this feel like your rightful place, on your knees serving me?”

Ceris moaned in response, only bringing Lilith closer to cuming. Just then Ceris seemed to find a nice sensitive spot and laid into it, causing Lilith’s hip to buck as her orgasm shot through her. Ceris fell to the floor, masturbating with blind lust as Lilith caught her breath from the intense orgasm. Just then Faris returned from her task.  
The Thrall said nothing at the scene and simply disrobed and walked over to the pair. She laid down, and with her great strength she lifted Ceris onto her, the young demons fat ass on her face and began eating her out. It took simply seconds for her to cum as well.

Lilith regained her composure and looked at the two sisters for a moment before making a decision.

“I think it's time to make it official,” She declared, “Both of you kneel before me.”

The two roused themselves and did so, bowing their heads in submission before their Mistress.

“Look at you both, so obedient and without a will, a shadow of what you once were, I love it,” Lilith proclaimed with a grin, “Now swear to me your obedience and servitude.”  
The sisters did, proclaiming their bodies, minds and very selves were Liliths to command and control forever. As the two rose Lilith ran a hand along both of their bellies. Black   
writing appeared on their skin over their wombs, brands that simply said LILITH.

“Now then,” the demon said “It's time to rest, because tomorrow we will need to plan my next move.”

Lilith left for her bedroom, and the sisters turned into theirs, awainting what was to come.


End file.
